Manganese ores form the starting material for the production of manganese based chemicals such as Electrolytic Manganese Dioxide (EMD), Electrolytic Manganese Metal (EMM), Chemical Manganese Dioxide (CMD) or Manganese Sulphate. Low Carbon Ferro Manganese, High Carbon Ferro Manganese and Silico Manganese are some of the Ferro Alloys produced from manganese ores. For the production of manganese based chemicals or ferro alloys such as Low Carbon Ferro Manganese, naturally occurring manganese ores have to be first subjected to reduction roasting to convert the ores from higher oxides into lower oxides. For the production of High Carbon Ferro Manganese, naturally occurring manganese ores can be used directly provided such ores contain manganese and iron atleast in 5:1 ratio. In Ferruginous ores (that is naturally occurring manganese ores with high iron content) the Manganese to Iron ratio is generally less than 5:1 and hence removal of iron therefrom is necessary for further processing. When ferruginous manganese ores are subjected to reduction roasting, the higher iron oxide minerals also get reduced to lower oxide form and are amenable to removal by magnetic seperation thereby improving the manganese to iron ratio. The lower iron manganese ores thus obtained can be used as a starting material for the production of manganese based chemicals or ferro alloys. Lower oxides of manganese produced by reduction roasting are soluble in solvents like sulphuric acid or hydrochloric acid whereas naturally occurring manganese oxide ores are insoluble in such solvents. Therefore, dissolution efficiency of reduction roasted manganese ores is dependent on the degree of reduction. Hence the lower the degree of reduction, higher the wastage of manganese minerals during the production of manganese based chemicals.